1. Field of the Invention
This invention relates generally to an energy-transmitting apparatus, and, in particular, to an apparatus which can easily supply energy to an apparatus implanted in a living body, such as a human body.
2. Description of the Prior Art
As to apparatus implanted in the body, a cardiac pacemaker is typically known which uses a mercury battery or a lithium battery as an energy source. However, the lifetime of almost all of these batteries is less than two years, so that, previously, the battery had to be periodically exchanged in anticipation of the termination of the battery life. On all such occasions, a physician had to perform a surgical operation for replacement of the battery and the patient is forced to undergo pain and expense which would otherwise be unnecessary. Also, if the pacemaker itself has some trouble, it may abnormally consume power, so that the battery life would be caused to be unexpectedly shortened. Although, in such an emergency, the battery should be immediately exchanged, this may not be possible. As a result, the life, dependent on the pacemaker, is threatened because of the need for the surgical operation and battery exchange. These possibilities bring a feeling of mental uneasiness to the patient and also the possible aggravation of the disorder requiring the pacemaker.
An atomic battery having a long life is known, which battery utilizes a radioisotope (RI) as a power source. Such apparatus, however, requires a radiation shield made of lead to protect the body from the x-rays emitted from the RI. The atomic battery is, therefore, not used conventionally because of its great weight and high price.
It has been recognized that the above-mentioned problems could be solved by the use of an implanted chargeable battery that could be recharged from outside the body. However, such a solution has been heretofore unrealizable because there has been no energy-transmitting apparatus which can interconnect a source of energy outside the body to the battery implanted in the living body without injuring the body.